diff --git a/Data/Text/IO/SaferFileHandles.hs b/Data/Text/IO/SaferFileHandles.hs
--- a/Data/Text/IO/SaferFileHandles.hs
+++ b/Data/Text/IO/SaferFileHandles.hs
@@ -47,7 +47,7 @@
                                                    , hPutStrLn
                                                    )
 -- from regions:
-import Control.Monad.Trans.Region ( ParentOf )
+import Control.Monad.Trans.Region ( AncestorRegion )
 
 -- from safer-file-handles:
 import System.IO.SaferFileHandles ( RegionalFileHandle
@@ -61,23 +61,23 @@
 -------------------------------------------------------------------------------
 
 -- | Wraps: @Data.Text.IO.'T.hGetLine'@.
-hGetLine ∷ (pr `ParentOf` cr, MonadIO cr, ReadModes ioMode)
+hGetLine ∷ (pr `AncestorRegion` cr, MonadIO cr, ReadModes ioMode)
          ⇒ RegionalFileHandle ioMode pr → cr Text
 hGetLine = wrap E.hGetLine
 
 -- | Wraps: @Data.Text.IO.'T.hGetContents'@.
-hGetContents ∷ (pr `ParentOf` cr, MonadIO cr, ReadModes ioMode)
+hGetContents ∷ (pr `AncestorRegion` cr, MonadIO cr, ReadModes ioMode)
              ⇒ RegionalFileHandle ioMode pr → cr Text
 hGetContents = wrap E.hGetContents
 
 
 -- | Wraps: @Data.Text.IO.'T.hPutStr'@.
-hPutStr ∷ (pr `ParentOf` cr, MonadIO cr, WriteModes ioMode)
+hPutStr ∷ (pr `AncestorRegion` cr, MonadIO cr, WriteModes ioMode)
         ⇒ RegionalFileHandle ioMode pr → Text → cr ()
 hPutStr = wrap2 E.hPutStr
 
 -- | Wraps: @Data.Text.IO.'T.hPutStrLn'@.
-hPutStrLn ∷ (pr `ParentOf` cr, MonadIO cr, WriteModes ioMode)
+hPutStrLn ∷ (pr `AncestorRegion` cr, MonadIO cr, WriteModes ioMode)
           ⇒ RegionalFileHandle ioMode pr → Text → cr ()
 hPutStrLn = wrap2 E.hPutStrLn
 
diff --git a/Data/Text/Lazy/IO/SaferFileHandles.hs b/Data/Text/Lazy/IO/SaferFileHandles.hs
--- a/Data/Text/Lazy/IO/SaferFileHandles.hs
+++ b/Data/Text/Lazy/IO/SaferFileHandles.hs
@@ -47,7 +47,7 @@
                                                         , hPutStrLn
                                                         )
 -- from regions:
-import Control.Monad.Trans.Region ( ParentOf )
+import Control.Monad.Trans.Region ( AncestorRegion )
 
 -- from safer-file-handles:
 import System.IO.SaferFileHandles ( RegionalFileHandle
@@ -61,23 +61,23 @@
 -------------------------------------------------------------------------------
 
 -- | Wraps: @Data.Text.Lazy.IO.'T.hGetLine'@.
-hGetLine ∷ (pr `ParentOf` cr, MonadIO cr, ReadModes ioMode)
+hGetLine ∷ (pr `AncestorRegion` cr, MonadIO cr, ReadModes ioMode)
          ⇒ RegionalFileHandle ioMode pr → cr Text
 hGetLine = wrap E.hGetLine
 
 -- | Wraps: @Data.Text.Lazy.IO.'T.hGetContents'@.
-hGetContents ∷ (pr `ParentOf` cr, MonadIO cr, ReadModes ioMode)
+hGetContents ∷ (pr `AncestorRegion` cr, MonadIO cr, ReadModes ioMode)
              ⇒ RegionalFileHandle ioMode pr → cr Text
 hGetContents = wrap E.hGetContents
 
 
 -- | Wraps: @Data.Text.Lazy.IO.'T.hPutStr'@.
-hPutStr ∷ (pr `ParentOf` cr, MonadIO cr, WriteModes ioMode)
+hPutStr ∷ (pr `AncestorRegion` cr, MonadIO cr, WriteModes ioMode)
         ⇒ RegionalFileHandle ioMode pr → Text → cr ()
 hPutStr = wrap2 E.hPutStr
 
 -- | Wraps: @Data.Text.Lazy.IO.'T.hPutStrLn'@.
-hPutStrLn ∷ (pr `ParentOf` cr, MonadIO cr, WriteModes ioMode)
+hPutStrLn ∷ (pr `AncestorRegion` cr, MonadIO cr, WriteModes ioMode)
           ⇒ RegionalFileHandle ioMode pr → Text → cr ()
 hPutStrLn = wrap2 E.hPutStrLn
 
diff --git a/safer-file-handles-text.cabal b/safer-file-handles-text.cabal
--- a/safer-file-handles-text.cabal
+++ b/safer-file-handles-text.cabal
@@ -1,5 +1,5 @@
 name:          safer-file-handles-text
-version:       0.1.0.3
+version:       0.1.0.4
 cabal-version: >=1.6
 build-type:    Custom
 license:       BSD3
@@ -18,10 +18,10 @@
 
 Library
   GHC-Options: -Wall
-  build-depends: text                  >= 0.7 && < 0.10
-               , regions               >= 0.6 && < 0.8
+  build-depends: text                  >= 0.7 && < 0.11
+               , regions               >= 0.8 && < 0.9
                , transformers          >= 0.2 && < 0.3
                , explicit-iomodes-text >= 0.1 && < 0.2
-               , safer-file-handles    >= 0.6 && < 0.9
+               , safer-file-handles    >= 0.9 && < 0.10
   exposed-modules: Data.Text.IO.SaferFileHandles
                    Data.Text.Lazy.IO.SaferFileHandles